Why is the GUI not closing?

My goal : I am trying to make a script that opens a window when you click a GUI button the closes that window if it is visible when the button is clicked again. The problem: when i click the button again and again it just keeps printing level 1 complete and stops there it also opens the window., i get no errors in the output to.

a=script.Parent.Parent.Frame
b=script.Parent.Parent.Frame.VoteText
script.Parent.MouseButton1Click:connect(function()
          a.Visible=true
          b.Visible=true
          print("level 1 complete")
end)
function onClicked()
        a.Visible=false
        b.Visible=false
        print("level 3 complete")
    end

    if a.Visible==true and b.Visible==true then
             script.Parent.MouseButton1Click:connect(onClicked)
             print ("level 2 complete")
     else
              print("you failed")
    return end